Kate Spade, the iconic fashion designer, was found dead in an apparent suicide at her Upper East Side apartment Tuesday morning, police said. The 55-year-old designer hanged herself with a scarf and left a note, an NYPD spokesman said.

A housekeeper found Spade in the bedroom of her apartment at 850 Park Ave., the NYPD said. She was pronounced dead around 10:25 a.m.

The handbag mogul, who was married to actor David Spade’s brother Andy Spade, was having “family problems … in her relationship,” a police source told the New York Post.

The note, a witness account and the “physical state of the apartment” led police to believe Spade’s death was “a tragic case of apparent suicide,” NYPD Chief of Detectives Dermot Shea said.

“We’ll go from here and continue to look into the incident,” Shea said at an unrelated news conference.

Shea declined to comment on the contents of the note or Spade’s relationship with her husband.

Born Katherine Noel Brosnahan, Spade launched her eponymous handbag company with Andy Spade in New York City in 1993 after a stint as the fashion editor for the now-shuttered magazine Mademoiselle. She expanded the company to an international fashion brand that is sold in retail stores worldwide.

Spade sold her remaining shares in the brand in 2006 before launching a new label, Frances Valentine, in 2016. The parent company of the fashion house Coach purchased Kate Spade & Company last July for $2.4 billion.

Spade is survived by her husband and their 13-year-old daughter, Frances Spade. Her niece is Rachel Brosnahan, star of the Amazon TV series “The Marvelous Mrs. Maisel.”

“Kate will be dearly missed,” Julia Curry, a spokeswoman for Kate Spade New York, said in a statement. “Our thoughts are with Andy and the entire Spade family at this time.”

The news of Spade’s death shocked people on the Upper East Side.

Laurie, a woman who lives nearby, said Spade was a “beautiful, vibrant soul” who she sometimes saw walking on the street.

“You never know what torments people,” Laurie said. “What a shame.”

Abigail Moorhouse of Flatbush said Spade was “the talk” of the hair salon where she works about a block from the designer’s apartment.

“I think she was going through a lot,” Moorhouse said.

Several celebrities took to social media to mourn the loss of the fashion icon, share stories of what her work meant to them and offer condolences to her family.

“My grandmother gave me my first Kate Spade bag when I was in college,” Chelsea Clinton wrote on Twitter. “I still have it. Holding Kate’s family, friends and loved ones in my heart.”

“Depression does not discriminate and comes without warning,” wrote musician Josh Groban. “RIP Kate Spade. Love to her family.”

“Kate Spade and Co donated handbags to our scholars, so they’d show up at their internships looking great and feeling great,” rememberedjournalist Soledad O’Brian. “They always downplayed their gift, and maybe this sounds silly, but it was a big deal for our young women to show up to an important gig with a great bag.”

The fashion world also mourned Spade’s death.

The designer Kenneth Cole called her a “true visionary” who “left an indelible mark on the fashion industry.”

“She was a great talent who had an immeasurable impact on American fashion and the way the world viewed American accessories,” Diane von Furstenberg and Steven Kolb of the Council of Fashion Designers in America said in a joint statement.

Anyone struggling with mental health can get help by calling National Suicide Prevention Lifeline at 1-800-273-8255 or visiting this website. New Yorkers can also find resources by calling 1-888-NYC-WELL.

By Noah Manskar [Patch]